Preparing and Characterization for Caustic Calcined Magnesite and Its Effect on Quality of Green-Pellets

doi:10.12068/j.issn.1005-3026.2017.03.014

Abstract

Abstract: Caustic calcined magnesite was utilized as an additive for pellets. The charterers of caustic calcined magnesite and the effects of activity on the quality of green-pellets were analyzed when the magnesite was calcined in different conditions. The results showed that when the calcined temperature is lower or the calcined time is inadequate， the decomposition of magnesite is limited and the hydration activity is lower， while the calcined temperature is much higher or the calcined time is much longer， the activity is destroyed. In 800~850℃， the caustic calcined magnesite has good characteristics such as high hydration activity， small granularity， large specific surface area and small average diameter of crystal grain. Caustic calcined magnesite with high activity can improve the dropped strength (DS/Times) and compressive strength of green-pellet(CSGP/N)， and can enhance the burst temperature of green-pellet(t_b/℃)， especially， the burst temperature(t_b/℃)can be increased up to 150℃.

Key words: magnesite, additive, green-pellet, activity, specific surface area

CLC Number:

TF521

GAO Qiang-jian， JIANG Xin， SHEN Feng-man， LIU Chang-sheng. Preparing and Characterization for Caustic Calcined Magnesite and Its Effect on Quality of Green-Pellets[J]. Journal of Northeastern University Natural Science, 2017, 38(3): 370-374.

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